Zytiga

"The U.S. Food and Drug Administration today expanded the approved use of Zytiga (abiraterone acetate) to treat men with late-stage (metastatic) castration-resistant prostate cancer prior to receiving chemotherapy.

For Patients

Zytiga (abiraterone acetate) is given in combination with prednisone and is indicated for the treatment of patients with metastatic castration-resistant prostate cancer. Zytiga is prescribed in 250 mg dosage tablets. It is important that Zytiga be taken on an empty stomach. No food should be consumed for at least two hours before the dose of Zytiga is taken and for at least one hour after the dose of Zytiga is taken.

Zytiga may harm a developing fetus. Therefore, women who are pregnant or women who may become pregnant should not handle Zytiga without protection such as gloves. Patients should also be informed that it is not known whether abiraterone or its metabolites are present in semen. Patient should use a condom if having sex with a pregnant woman. The patient should use a condom and another effective method of birth control if he is having sex with a woman of child-bearing potential. These measures are required during and for one week after treatment with Zytiga.

Our Zytiga Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What is Patient Information in Detail?

Easy-to-read and understand detailed drug information and pill images for the patient or caregiver from Cerner Multum.

Clinical Trial Experience

Because clinical trials are conducted under widely
varying conditions, adverse reaction rates observed in the clinical trials of a
drug cannot be directly compared to rates in the clinical trials of another
drug and may not reflect the rates observed in clinical practice.

Two randomized placebo-controlled, multicenter clinical
trials enrolled patients who had metastatic castration-resistant prostate
cancer who were using a gonadotropin-releasing hormone (GnRH) agonist or were
previously treated with orchiectomy. In both Study 1 and Study 2 ZYTIGA was
administered at a dose of 1,000 mg daily in combination with prednisone 5 mg
twice daily in the active treatment arms. Placebo plus prednisone 5 mg twice
daily was given to control patients.

Table 1 shows adverse reactions on the ZYTIGA arm in
Study 1 that occurred with a ≥ 2% absolute increase in frequency compared
to placebo or were events of special interest. The median duration of treatment
with ZYTIGA was 8 months.

Study 2: Metastatic CRPC Prior
to Chemotherapy

Study 2 enrolled 1088 patients
with metastatic CRPC who had not received prior cytotoxic chemotherapy.
Patients were ineligible if AST and/or ALT ≥ 2.5X ULN and patients were
excluded if they had liver metastases.

Table 3 shows adverse reactions
on the ZYTIGA arm in Study 2 that occurred with a ≥ 2% absolute increase
in frequency compared to placebo. The median duration of treatment with ZYTIGA
was 13.8 months.

Table 3: Adverse Reactions in ≥ 5% of Patients on
the ZYTIGA Arm in Study 2

Table 4 shows laboratory
abnormalities that occurred in greater than 15% of patients, and more
frequently ( > 5%) in the ZYTIGA arm compared to placebo in Study 2. Grade 3-4
lymphopenia (9%), hyperglycemia (7%) and high alanine aminotransferase (6%)
occurred at a greater than 5% rate in the ZYTIGA arm.

Table 4: Laboratory
Abnormalities in > 15% of Patients in the ZYTIGA Arm of Study 2

Laboratory Abnormality

Abiraterone
(N=542)

Placebo
(N=540)

Grade 1-4 %

Grade 3-4 %

Grade 1-4 %

Grade 3-4 %

Hematology

Lymphopenia

38.2

8.7

31.7

7.4

Chemistry

Hyperglycemia1

56.6

6.5

50.9

5.2

High ALT

41.9

6.1

29.1

0.7

High AST

37.3

3.1

28.7

1.1

Hypernatremia

32.8

0.4

25.0

0.2

Hypokalemia

17.2

2.8

10.2

1.7

1Based on non-fasting blood draws

Cardiovascular Adverse
Reactions

In the combined data for
studies 1 and 2, cardiac failure occurred more commonly in patients treated
with ZYTIGA compared to patients on the placebo arm (2.1% versus 0.7%). Grade
3-4 cardiac failure occurred in 1.6% of patients taking ZYTIGA and led to 5
treatment discontinuations and 2 deaths. Grade 3-4 cardiac failure occurred in
0.2% of patients taking placebo. There were no treatment discontinuations and
one death due to cardiac failure in the placebo group.

In Study 1 and 2, the majority
of arrhythmias were grade 1 or 2. There was one death associated with
arrhythmia and one patient with sudden death in the ZYTIGA arms and no deaths
in the placebo arms. There were 7 (0.5%) deaths due to cardiorespiratory arrest
in the ZYTIGA arms and 3 (0.3%) deaths in the placebo arms. Myocardial ischemia
or myocardial infarction led to death in 3 patients in the placebo arms and 2
deaths in the ZYTIGA arms.

Post Marketing Experience

The following additional
adverse reactions have been identified during post approval use of ZYTIGA.
Because these reactions are reported voluntarily from a population of uncertain
size, it is not always possible to reliably estimate their frequency or
establish a causal relationship to drug exposure.